Jenn, Lou is right--the arms are designed to work in zero-G environments, and are too heavy to do any lifting in Earth's 1G. "Lightweight" refers to the new NG Small Canadarm, the one that will do repairing and refueling of satellites in space.

Beth, while checking out the latest, NG Canadarm, I was looking at all the cool historical space photos. Then I started reading the caption data and realized that Canadarm, in one form or another, had been part of so many key historical events in space. That's how the idea for this slideshow was born.

Ann, this slide show brings back lots of memories. One of my last aerospace projects was working on the Canadarm2. I was with a company involved with supporting the software used to control the arm. I was at their plant and got to touch one of the shuttle arms while it was being refurbished on the ground. That was back in 1992, by the way.

On thing that was interesting is the genesis of the companies involved. I was doing a project for Spar Aerospace. MacDonald, Dettwiler and Associates Ltd. was a subcontractor we also worked with. Now Spar is part of MacDonald, Dettwiler and Associates Ltd. It is funny how the consolidation in the industry happens.

Ann, The end effector used to grab hardware and spacecraft is not what normally comes to mind when one thinks of "robotic" arms (a typical mechanical gripper). Do you kno how the 3-wire snare used on all of the Canadarms came to be the standard for US space operations?

The first image of the slide show looks like the arm being tested / demonstrated. I believe the motors that move the arms are actually quite small. If I remember correctly, the arm can't really support itself in a 1-G gravity field.

Are those blue units part of the supporting rig, air-cushion supports that permit the arm to move freely in a horizontal plane?

With the photos stacked up like that, it's pretty incredible to see how far the space arm has come in terms of form, functionality, and in particular, size. Specifically, it strikes me as to how large the robotic manipulators are when viewed in the first slide in some sort of facility on earth vs. when they are viewed within the context of the vastness of outer space. Cool slide show.

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